Methine dyestuffs and their manufacture



Patented Apr. 8, 1952 UNITED STATES METHINE DYESTUFFS AND THEIRMANUFACTURE George Schwarz, Rochester, N. Y., and Polydoor Frans DeSmet, Wilrijk-Antwerp, Belgium, assignors to Gevaert Photo-Producten N.V., Mortsel-Antwerp, Belgium, a company of Belgium 2,592,196 PATENTOFFICE No Drawing. Application August 29, 1947, Serial No. 771,402. InGreat Britain December 28,

Section 1, Public Law 690, August 8, 1946 Patent expires December. 28,1959 Claims.

X represents a halogen atom 11. represents a positive integer of from 1to 2 L represents a member selected from the group consisting ofmethylene and substituted methylene and optionally treating the productswith a. salt containing an acid radical other than a halogen.

The preparation of these compounds is described in our co-pendingapplication, Ser. No. 771,401.

These starting compounds are treated with (a) condensing agents known tobe used in the formation of methine dyestuffs from cycloammonium salts,or with (b) products which supply the central carbon atoms of methinedyestufis, or with (c) intermediate products known to be used togetherwith cycloammonium salts in the formation of methine dyestufis in thepresence of such condensing agents or (d) with aromatic aldehydes.

Examples of condensing agents as defined under (a) are acetic anhydrideand triethylamine;

Examples of products which supply the central carbon atoms of .methinedyestuffs as defined under (12) are: ortho-carboxyl esters,imino-esters, alkyl-esters of arylated thio-imido (U. S. P. 2,107,379),esters or salts of nitrous acid.

Examples of intermediate products as defined under (0) are: halogeno-,alkylmercapto-, aralky1mercapto-, arylmercapto-, alkylseleno-,arylseleno-, aralkylseleno derivatives or halogeno-, alkylmercapto-,aralkylmercapto-, arylmercapto-, alkylseleno-, aralkylseleno-,arylseleno-, anilino-, or acetanilido-, acetamino-, vinylene-, anilino-,or acetanilido methylene-, formylor thioformyl methylene-, acylorthioacyl methylene-, (betaalkylmercapto-beta-alkyl)vinyl-, or (beta-sub-2 stituted alkylmercapto-beta-alkyl')vinyl-,(betaarylmercapto-betaalkyl) vinyl-, (beta-dialkylmercapto) vinyl-,(beta-selenoalkyl-beta-alkyl-) vinyl-, or(beta-substituted-selenoalkyl-beta-alkyl)vinyl derivatives ofnitrogenous rings.

Example 1 A mixture of 3.2 g. N-ethyI-Z-thio-quinolinedimethylsulphateand 3 g. of the condensation product of 2-methyl-3:4-benzobenzthiazoleand ethylene bromide is dissolved by refluxing in 30 cm. of dry ethylalcohol. After the addition of 1.3 cm. of triethylamine the refluxing iscontinued during 5 minutes. The dyestuff is precipitated by the additionof ether and purified by recrystallisation from ethyl alcohol. Thealcoholic solution of the dyestufi hasan absorption maximum at a wavelength of about 515 and a sensitizing maximum at about 540 in, (broad).

Example 2 A mixture. of 3.2 g. N-ethyl-2-thio quinoline dimethylsulphateand 2.7 g. of the condensation product of Z-methyl benzthiazole andtrimethylene bromide are, dissolved by refluxing in 40 cm. of dry ethylalcohol. 1.3 cm. of triethylamine is added and the mixture boiled forabout 10 minutes. The. dyestufi is precipitatedwith ether andrecrystallized from ethyl alchohol. The alcoholic solution of thedyestufi has an absorption maximum at about 490 III/1.. sensitizingmaximum at about 525 mp.

Example 3 Example 4 3.2 g. of the condensation product of Z-methyl-3:4-benzobenzthiazole and trimethylene bromide are dissolved in 20 cm.of dry pyridine. 3 cm. of ethylester of otho-formic acid are added andthe mixture boiled. for about 1 hour. The dyestufi is precipitated witha solution of potassium bromide and recrystallized from ethylv alcohol.

Absorption maximum' in alcoholic solution at about 600 m sensitizing:maximum at about 3 Example 5 l5 cm. dry pyridine, 5 cm. ethylester oforthoacetic acid and 3.2 g. of the condensation product of2-methyl-3:4-benzobenzthiazole and trimethylene bromide are boiled for 1hour. The dyestufi is precipitated with a solution of potassium iodideand recrystallized from ethyl alcohol. Absorption maximum in alcoholicsolution at about 585 m sensitizing maximum at about 620 m Example 6 3.2g. of 2-acetanilidovinyl-4-dimethylaminobenzthiazole ethyl iodide and2.7 g. of the condensation product of Z-methylbenztlfiazole andtrimethylene bromide are dissolved in 30 cm? of dry pyridine and boiledfor about 1 hour. After precipitation with ether the dyestufi ispurified by recrystallization from ethyl alcohol. This dyestufi shows anabsorption maximum at about 590 m (alcoholic solution) and a broadsensitizing maximum from 640 to 680 m Example 7 4.5 g. of2-acetanilidovinylbenzthiazolethyliodide and 4.5 g. of the condensationproduct of 2-methyl-3:4-benzobenzthiazole and trimethylene bromide aredissolved in 30 cm. of dry pyridine and refluxed for a quarter of anhour. The dyestuff is precipitated with a solution of potassium iodideand recrystallized from methyl alcohol. Absorption maximum in alcoholicsolution at about 575 m sensitizing maximum at about 620 m Example 8 4g. dimethylsulphate of[N-ethyl-5:6-benzobenzthiazolidene methyl]methylthioketone (pending British specification 141/40) and 3 g. of thecondensation product of 2-methyl-3z4-benzobenzthiazole and ethylenebromide are dissolved by refluxing in 60 cm. of dry ethyl alcohol, 1.4cm. of triethylamine are added and the mixture is boiled for 2 minutes.The dyestuff is precipitated with a solution of potassium bromide. Thecrude dyestuff is washed with water and alcohol. Further purificationwas obtained by recrystallization from ethyl alcohol. Absorption maximumat about 580 ml. sensitizing maximum at about 640 my.

Example 9 4.5 g. 2-benzoylmethylene-N-ethyl-5-methyl-1:Z-dihydrothiodiazole-l:3z4- and 4 g. of the condensation product of2:5-dimethylthiodiazole and ethylene bromide are boiled in 40 cm. aceticanhydride for 20 minutes. The dyestuff is precipitated with ether andnext, after dissolving in alcohol, precipitated with an aqueous solutionof sodium perchlorate and recrystallised from alcohol.

Example 10 4.5 g. dimethyl sulphate of 2-thio acetylmethylene-N-ethyl-l:2-dihydrobenzthiazole and 3.5 g. of the condensation product of2-methylbenzselenazole and ethylene bromide are boiled for 2 minutes in30 cm. absolute alcohol with 1.7 cm. triethylamine by the use of areflux cooler. After precipitation with ether, the dyestufi isre-dissolved in alcohol and precipitated with an aqueous 10 percent KIsolution and recrystallised from alcohol.

While the detailed description refers to the production of certainspecific bodies, it is to be understood that the invention extends toprocesses for producing generally similar bodies within the scope ofthis specification, and to the use of such bodies in the production ortreatment of photographic emulsions and to photographic materials, theemulsions of which have been sensitized with such dyestuffs.

We claim:

1. Process for the manufacture of a new methine dyestufi which comprisestreating a heterocyclic compound corresponding to the formula ,r Y C-CH;H|C-O Y wherein:

Y represents the non-metallic atoms necessary to complete a memberselected from the group consisting of 5-membered and G-memberedheterocyclic rings and of the same 5-membered and G-memberedheterocyclic rings having a fused-on arylene group, while B representsalkyl,

X represents an acid residue,

Q represents a member selected from the group consisting of S-alkyl,

alkyl 2. The dyestufi corresponding to the formula:

and

3. The dyestuif corresponding to the formula:

ilon=on-cn=l ijo V 5. A bis-cyanine dye of the general formula:

wherein Z and Z' constitute the atoms necessary to complete an azolenucleus, Q is a trivalent bridging radical of the type usual in cyaninedyes radical which forms a conjugated chain of atoms between theintracyclic nitrogen atoms of the two adjacent azole nuclei, A is apolymethylene radical, R is a hydrocarbon radical taken from the groupconsisting of alkyl and aralkyl radicals, and X is the negative radicalof an acid.

GEORGE SCHWARZ. POLYDOOR FRANS DE SMET.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 2,418,748 Bayley Apr. 8, 19472,425,772 Wilson Aug. 19, 1947 2,425,773 Wilson Aug. '19, 1947 2,425,774Wilson Aug. 19, 1947 2,465,412 Wilson Mar. 29, 1949 2,465,774 WilsonMar. 29, 1949

5. A BIS-CYANINE DYE OF THE GENERAL FORMULA: